A thiol probe for measuring unfolded protein load and proteostasis in cells.

When proteostasis becomes unbalanced, unfolded proteins can accumulate and aggregate. Here we report that the dye, tetraphenylethene maleimide (TPE-MI) can be used to measure cellular unfolded protein load. TPE-MI fluorescence is activated upon labelling free cysteine thiols, normally buried in the core of globular proteins that are exposed upon unfolding.

Uptake, Distribution, and Bioimaging Applications of Aggregation-Induced Emission Saponin Nanoparticles in Arabidopsis thaliana.

The application of aggregation-induced emission luminogens (AIEgens) has heralded a new age in the analysis of subcellular events and has overcome many of the limitations of conventional fluorescent probes. Despite the extensive literature investigating AIEgens in mammalian cells, few reports exist of their bioimaging applications in plant cells. In this report, we describe the first systematic investigation of the uptake, distribution, and bioimaging applications of AIEgens and AIE saponin nanoparticles in the plant model system Arabidopsis thaliana.

AIEgen-based theranostic system: targeted imaging of cancer cells and adjuvant amplification of antitumor efficacy of paclitaxel.

Photosensitizers are generally treated as key components for photodynamic therapy. In contrast, we herein report an aggregation-induced emission luminogen (AIEgen)-based photosensitizer (TPE-Py-FFGYSA) that can serve as a non-toxic adjuvant to amplify the antitumor efficacy of paclitaxel, a well-known anticancer drug, with a synergistic effect of "0 + 1 > 1". Besides the adjuvant function, TPE-Py-FFGYSA can selectively light up EphA2 protein clusters overexpressed in cancer cells in a fluorescence turn-on mode, by taking advantage of the specific YSA peptide (YSAYPDSVPMMS)-EphA2 protein interaction.

An AIE-active fluorescence turn-on bioprobe mediated by hydrogen-bonding interaction for highly sensitive detection of hydrogen peroxide and glucose.

An AIE-active "turn-on" bioprobe is designed for hydrogen peroxide detection based on an imine-functionalized tetraphenylethene derivative. The linear fluorescence response enables quantification of hydrogen peroxide with superior sensitivity and selectivity. Meanwhile, glucose assay is also realized by taking advantage of GOx/glucose enzymatic reaction.

Activatable Fluorescent Nanoprobe with Aggregation-Induced Emission Characteristics for Selective In Vivo Imaging of Elevated Peroxynitrite Generation.

An activatable fluorescent nanoprobe with aggregation-induced emission signature is developed. The nanoprobe is nonfluorescent, but can be induced to emit intensely after reaction with peroxynitrite forming an intramolecular hydrogen bond. Excellent performance for selective in vivo imaging of inflammation with elevated peroxynitrite generation and efficient visualization of in vivo treatment efficacy of anti-inflammatory agents is demonstrated.

AEE-active cyclic tetraphenylsilole derivatives with ∼100% solid-state fluorescence quantum efficiency.

Two new strongly AEE active (I/I0 ≈ 94) tetraphenylsilole-containing cyclosiloxanes with cyan emissions (λem = 500 nm) and ∼100% solid state fluorescence quantum yields are reported. The intra- and intermolecular C-Hπ interactions in the crystal play a major role in the observed high solid state fluorescence quantum yields.

Effect of ionic interaction on the mechanochromic properties of pyridinium modified tetraphenylethene.

A pyridinium modified tetraphenylethene-based salt shows aggregation-induced emission enhancement properties and irreversible mechanochromic behaviours.

A ratiometric fluorescent probe based on ESIPT and AIE processes for alkaline phosphatase activity assay and visualization in living cells.

Alkaline phosphatase (ALP) activity is regarded as an important biomarker in medical diagnosis. A ratiometric fluorescent probe is developed based on a phosphorylated chalcone derivative for ALP activity assay and visualization in living cells. The probe is soluble in water and emits greenish-yellow in aqueous buffers.

Two-dimensional metal-organic framework with wide channels and responsive turn-on fluorescence for the chemical sensing of volatile organic compounds.

We report a 2D layered metal-organic framework (MOF) with wide channels named NUS-1 and its activated analogue NUS-1a composed of Zn4O-like secondary building units and tetraphenylethene (TPE)-based ligand 4,4'-(2,2-diphenylethene-1,1-diyl)dibenzoic acid. Due to its special structure, NUS-1a exhibits unprecedented gas sorption behavior, glass-transition-like phase transition under cryogenic conditions, and responsive turn-on fluorescence to various volatile organic compounds. Our approach using angular ligand containing partially fixed TPE units paves a way toward highly porous MOFs with fluorescence turn-on response that will find wide applications in chemical sensing.

A dual-mode fluorescence "turn-on" biosensor based on an aggregation-induced emission luminogen.

A novel dual-mode fluorescence "turn-on" probe is developed based on a phosphorylated tetraphenylethene (TPE) derivative bearing aggregation-induced emission (AIE) characteristics. The probe is weakly emissive in aqueous solution but its fluorescence is significantly enhanced in the presence of protamine or alkaline phosphatase (ALP). The cationic protamine interacted with the anionic phosphate group of the amphiphilic probe via electrostatic interaction and induced micelle formation.

BSA-tetraphenylethene derivative conjugates with aggregation-induced emission properties: fluorescent probes for label-free and homogeneous detection of protease and α1-antitrypsin.

Herein, BSA-tetraphenylethene derivative conjugates with aggregation-induced emission (AIE) properties were constructed and used as fluorescent probes for label-free detection of protease and α1-antitrypsin. Conjugated AIE probes were formed based on the electrostatic induced assembly between an ammonium cation of quaternized tetraphenylethene salt and carboxyl anion groups of BSA. While water soluble quaternized tetraphenylethene salt showed very low fluorescence in its well-dispersed state, obvious enhancement in the fluorescence of the aggregated tetraphenylethene derivative on the BSA templates was achieved due to the abnormal aggregation-induced emission properties of tetraphenylethene.

Label-free fluorescence detection of mercury(II) and glutathione based on Hg2+-DNA complexes stimulating aggregation-induced emission of a tetraphenylethene derivative.

Herein, a sensitive and selective sensor for mercury(II) and glutathione based on the aggregation-induced emission (AIE) of a tetraphenylethene derivative stimulated by Hg(2+)-DNA complexes is reported. Aggregation complexes of AIE probes, quaternized tetraphenylethene salt and anti-Hg(2+) aptamer ssDNA, were formed based on the electrostatic interactions between the ammonium cation of AIE probes and the backbone phosphate anions of DNA. In the presence of target Hg(2+), the aptamer ssDNA with thymine (T)-rich sequences selectively bound with Hg(2+) to form an Hg(2+)-bridged T base pair and the ssDNA changed into a hairpin-like structure.

Fluorescence detection of alkaline phosphatase activity with β-cyclodextrin-modified quantum dots.

An alkaline phosphatase activity detection system was constructed based on the different quenching effect of the enzyme substrate and product on the β-CD-functionalized CdTe QDs.

Highly soluble PEGylated pyrene-gold nanoparticles dyads for sensitive turn-on fluorescent detection of biothiols.

Highly soluble fluorescent pyrene derivative with substantially improved fluorescence intensity in aqueous buffer was obtained via PEGylation strategy. The highly soluble PEGylated pyrene (PEO-Py) non-covalently adsorbed onto the surface of gold nanoparticles (Au NPs) to form dyads with quenched fluorescence due to highly efficient energy transfer between PEO-Py and Au NPs. The PEO-Py/Au NPs dyads were used for the sensitive turn-on fluorescent detection of biothiols.